Applicazioni nfc

How does NFC technology work?
Near Field Communication is based on inductive-coupling, where loosely coupled inductive circuits share power and data over a distance of a few centimeters. NFC devices share the basic technology with proximity (13.56MHz) RFID tags and contactless smartcards, but have a number of key new features.

How does NFC technology build on existing technologies?
NFC is based on pre-existing contactless payment and ticketing standards that are used on a daily basis by millions of people using their devices worldwide. These standards determine not only the "contactless" operating environment, such as the physical requirements of the antennas, but also the format of the data to be transferred and the data rates for that transfer.

Which standards organizations acknowledge NFC technology?
NFC Standards are acknowledged by ISO/IEC (International Organization for Standardization / International Electrotechnical Commission), ETSI (European Telecommunications Standards Institute), and ECMA (European association for standardizing information and communication systems).

What ISO/IEC standards do the NFC Forum specifications support?
NFC Forum compliant devices in NFC Forum Reader/Writer mode must support the RF requirements for ISO/IEC 14443A, ISO/IEC 14443 B and FeliCa as outlined in the relevant parts in the ISO 18092.

What are the data transmission rates?
NFC data transmission is measured in Kilo Bits Per Second (kbps). The NFC standard supports varying data rates, again to ensure interoperability between pre-existing infrastructure. The current data rates are 106kbps, 212kbps, and 424kbps.

What is the difference between an NFC-enabled device and an NFC tag?
An NFC-enabled device can operate in reader/writer and peer-to-peer mode, and may operate in card emulation mode. An NFC tag is typically a passive device (for example, integrated in a smart poster) that stores data that can be read by an NFC-enabled device.

What is the difference between a card and a tag?
A card and a tag are technically the same. However, contactless cards used in ticketing and payment today include additional technology to store secure data.

How is NFC different from or related to other wireless/RF technologies?
Near Field Communication (NFC) is a standards-based, short-range (a few centimeters) wireless connectivity technology that enables simple and safe two-way interactions between electronic devices, allowing consumers to perform contactless transactions, access digital content, and connect electronic devices with a single touch.

Bluetooth wireless technology was designed to replace cables between cell phones, laptops, and other computing and communication devices within a 10-meter range.

Wi-Fi technology was designed and optimized for Local Area Networks (LAN); it provides an extension or replacement of wired networks for dozens of computing devices within a +100-meter range.

ZigBee wireless technology is a standard enabling control and monitoring capabilities for industrial and residential applications within a +100-meter range.

IrDA is a short range (< 1 meter), line-of-sight communication standard for exchange of data over infrared light. IrDA interfaces are frequently used in computers and mobile phones.

RFID (Radio Frequency Identification) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags. An RFID tag is a small object that can be attached to or incorporated into a product. RFID tags contain silicon chips to enable them to receive and respond to queries from an RFID reader/writer.

Contactless smart cards incorporate a chip (microprocessor) that communicates with a card reader through RFID technology. Examples of contactless smart card communications are ISO/IEC 14443 and FeliCa, which allow communications at distances up to 10 cm.

What are the operating modes of NFC devices?
NFC devices are unique in that they can change their mode of operation to be in reader/writer mode, peer-to-peer mode, or card emulation mode. The different operating modes are based on the ISO/IEC 18092 NFC IP-1 and ISO/IEC 14443 contactless smart card standards.

• In reader/writer mode, the NFC device is capable of reading NFC Forum-mandated tag types, such as in the scenario of reading an NFC Smart Poster tag. The reader/writer mode on the RF interface is compliant to the ISO 14443 and FeliCa schemes.
  
• In Peer-to-Peer mode, two NFC devices can exchange data. For example, you can share Bluetooth or WiFi link set up parameters or you can exchange data such as virtual business cards or digital photos. Peer-to-Peer mode is standardized on the ISO/IEC 18092 standard.
  
• In Card Emulation mode, the NFC device appears to an external reader much the same as a traditional contactless smart card. This enables contactless payments and ticketing by NFC devices without changing the existing infrastructure.